Erectile dysfunction

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much more. Try it free today!In erectile dysfunction, an individual is
unable to develop or maintain an erectionduring sex. This disorder is also called impotence and
like other sexual dysfunction, this conditionbecomes more common with age. Sex can be important within relationships,
so erectile dysfunction often carries withit emotional and psychological stigma. In both males and females, sexual activity
involves a sequence of events called the sexualresponse cycle. This cycle has four phases, excitement, plateau,
orgasm, and resolution. During the excitement phase, muscle tension,
heart rate, and blood flow to the genitalsincreases. In males, this is called an erection. When these reach the maximum level, it’s
called the plateau phase. Next, the accumulated sexual tension gets
released during orgasm, causing ejaculationin males. Immediately after orgasm comes the resolution
phase, where the body slowly returns to itsoriginal, un-excited state. Alright, let’s take a closer look at the
penis which is made of three long cylindricalbodies: the corpus spongiosum that surrounds
the penile urethra, and the two corpora cavernosamade of erectile tissue. The corpora cavernosa are wrapped in a fibrous
coat called the tunica albuginea, and eachcorpus cavernosum is made up of blood-filled
spaces called the cavernosal spaces. These areas are lined with endothelial cells
surrounded by smooth muscle. Running down the centre of each corpus cavernosum
is a large artery called the deep artery whichgives off smaller arteries that supply the
cavernosal spaces. Next, blood get drained from these spaces
by small emissary veins, which drain intothe deep dorsal vein. This vein then carries the blood back into
the systemic circulation. Now, the penis receives both somatic and autonomic
innervation through the cavernous nerves,which innervate both the corpus spongiosum,
and the corpora cavernosa. You can remember the functions of these fibers
with the mnemonic “point and shoot. ”“Point” is erection and it’s caused
by “P,” or parasympathetic fibers. “Shoot” is ejaculation and the “S”
is for sympathetic. Now, an erection can happen in two ways, either
by physical stimulation of the penis or genitals,called reflex erection, or by becoming emotionally
stimulated by a thought, called psychogenicerection. In both cases, the parasympathetic nerve fibers
in the cavernosal spaces release acetylcholinefrom their nerve endings. The acetylcholine bind to muscarinic receptors
on endothelial cells, which activates theenzyme nitric oxide synthase. Nitric oxide synthase converts the amino acid
arginine into citrulline and nitric oxide. The nitric oxide diffuses into the nearby
smooth muscle cells, and activates guanylatecyclase, which converts GTP molecules to cGMP. This leads to a fall in intracellular calcium
levels causing the smooth muscles to relax,and allowing the cavernosal spaces to expand
and fill with blood. The corpora cavernosa grow in size, and compress
the veins, making it harder for blood to leave. With more blood coming in but very little
blood leaving, the penis can maintain an erection. Erectile dysfunction leads to an inability
to develop and maintain a full erection. Causes include psychological ones like stress,
performance anxiety, and depression. In addition, there are a number of physiologic
causes as well. The most common physiologic cause for erectile
dysfunction is an inadequate blood supplydue to atherosclerosis and blood vessel damage
from hypertension. Atherosclerosis is caused by the buildup of
atheromatous plaques that can harden the arteriessupplying the penis, which makes it difficult
for them to dilate. Hypertension causes wear and tear in the endothelial
cells, and decrease their ability to producenitric oxide. Another condition that can also damage the
arteries is diabetes mellitus. High glucose levels can cause hyaline arteriolosclerosis
in the small arterioles in the penis. This is where the arteriole walls develop
hyaline deposits, which makes it harder forthem to dilate. It also builds up in the capillaries causing
the basement membrane to thicken which makesit harder for oxygen to efficiently move from
the vascular space to the tissues, causinghypoxia and death of the smooth muscle cells. This hypoxia also causes the parasympathetic
nerve fibers to die off. Damaged parasympathetic nerve fibers can’t
release acetylcholine, so there’s less nitricoxide synthase activation, and less nitric
oxide is produced. Also, conditions like stroke, multiple sclerosis,
and back or pelvic trauma can directly damagethe nerves, leading to erectile dysfunction. Next, endocrine dysfunctions that causes testosterone
levels to fall, like hypogonadism, can causeerectile dysfunction. This happens because low testosterone levels
are associated with lower levels of nitricoxide synthase, which causes less nitric oxide
to be produced, and less smooth muscle relaxation. Since testosterone production decreases with
age, it’s normal for erections to becomemore difficult to achieve and maintain later
in life. Finally, many medications can cause erectile
dysfunction as a side effect. These include diuretics because they leave
less fluid in your circulation, making itdifficult to achieve an erection, and medications
like antidepressants and methadone, but thosemechanisms are not as well understood. There is no specific test to diagnose erectile
dysfunction, so the diagnosis largely relieson the sexual experiences of the individual. Careful questioning of psychological stressors
as well as blood tests to check for testosteroneand glucose levels, a neurological assessment,
and duplex ultrasound to evaluate blood flowand atherosclerosis can be done to investigate
the cause of erectile dysfunction. Treatment of erectile dysfunction largely
focuses on addressing the underlying cause. In terms of medications, PDE-5 inhibitors,
like sildenafil can be used. These medications inhibit the PDE-5 enzyme
in endothelial cells which normally breaksdown cGMP, leading to higher levels of cGMP. That allows for more smooth muscle relaxation
which facilitates an erection. Sometimes, vacuum erection devices can be
used. These devices apply negative pressure around
the penis which can help draw in blood toachieve an erection. Finally, surgical procedures like prosthetic
implants can be embedded into the penis. They does not cause erections but it could
help keep the penis rigid. All right, as a quick recap, erectile dysfunction
is the inability to develop or maintain anerection and it could have psychological or
organic causes. Organic causes can be due to cardiovascular
disorders like hypertension, neurologicalproblems like those caused by diabetes, or
hormonal dysfunction where testosterone levelsdecrease. Various medications, like diuretics can also
cause erectile dysfunction as an side effect. There’s no specific test to diagnose erectile
dysfunction, so, diagnosis is typically gearedat detecting pre-existing causes. Treatment includes PDE-5 inhibitors like sildenafil,
vacuum erection devices, and surgery.